/Engine/Source/Editor/SceneOutliner/Public/SceneOutlinerFilters.h
Overridden to ensure we only ever haveFSceneOutlinerFiltersadded
int32 Add ( const [TSharedPtr](API\Runtime\Core\Templates\TSharedPtr)< [FSceneOutlinerFilter](API\Editor\SceneOutliner\FSceneOutlinerFilter) > & Filter )